1. Field of the Invention
The present invention relates generally to a system and method for automatically filling multiple orders of different quantities and types of items. More specifically, a system is provided wherein the quantities of any Stock Keeping Unit (SKU) for an order may be less than the standard package quantity for that particular SKU such that redistribution of SKU's into multiple transport units is required, A planning method is implemented for arranging orders into a plurality of transport units containing mixed SKU types, and sequencing the processing of SKU packages and transport units so that the orders are placed by a robotic workcell with a fixed quantity of transport unit fill positions.
2. Description of Related Art
Problems associated with automatically placing a plurality of different SKUs, i.e., brands of items, in a single storage unit are well known in the art. The problem becomes more difficult to solve when the types and quantities of SKUs to be placed in the storage units vary between orders. That is, a first order may require different quantities of several different SKUs and a subsequent order may call for different quantities of the same SKUs, or different quantities of completely different SKUs. Additionally, it can be seen that a problem exists when an order calls for a specific quantity of SKU that is less than the quantity in which the SKU is normally supplied. For example, an order may call for two units of a particular SKU (brand A) and four units of a second SKU (brand B), but brand A is supplied in cases of twelve units. Thus, ten additional units of brand A need to be placed before continuing on to brand B. In order to maximize use of a placing robot, the robot should complete placement of brand A prior to placing any units of brand B.
U.S. Pat. No. 4,588,349 discusses a method of automatically filling a kit with required parts. The parts are held in a container and stored in trays which are placed at a transfer location. A robot removes the selected container and empties it into a kit box. U.S. Pat. No. 5,029,095 describes a system that assembles multiple components wherein the components are placed in one of a plurality of bins and a display indicates a complete kit of parts to be subsequently assembled. U.S. Pat. No. 4,988,256 discusses an apparatus and method of compiling parts into individual kits. An apparatus wherein parts are singulated onto multiple feeders through a gate such that the required parts are transported to a workstation. IBM TDB "Dynamic Database" discusses a database used to manage the data flow through an automatic packaging and palletizing system. A packaging line is divided into zones with an associated computer for each zone. A kitting database is transferred from each computer to the subsequent computer as the items being packaged moves between zones. IBM TDB "Database Structure" describes an automatic parts inventory system. Inventory is stored on pallets that are located in aisles. Information is stored for the pallets based on data indexes in fields in the database. These fields include information such as the types of parts on the pallet, vendor that supplied the parts, date the parts were received, location of the pallet, oldest and newest location of a particular part, and the like.
It can be seen that conventional techniques do not provide any near optimal techniques for placing partial orders by ensuring that the most difficultly placed SKU (brand) is put in the oldest transport units before continuing to place subsequently desired brands.